CommandLine: using cl::Positional with enum

Hi,

I’ve been trying to code through CommandLine the options I want my tool accepts, but I find find quite impossible to achieve robustly what I need.

Look, I want the tool accepts a list of arguments in a particular order. For this goal, I know the cl::Positional flag. But, the problem is that the first argument must be one of a set of options. In my case, only the three next commands are possible:

myTool option1
myTool option2 arg1 arg2
myTool option3 arg1

and I don’t want a different order is possible, for instance, this is not permitted:
myTool arg2 option2 arg1
So, I thought about using an enum for this first argument:

enum OptLevel{
option1, option2, option3
};

cl::opt OptionsLevel(cl::Positional, cl::desc(“Choose one of these options:”),
cl::values(
clEnumVal(option1, “…”),
clEnumVal(option2, “…”),
clEnumVal(option3, “…”),
clEnumValEnd)
);

After that, the rest of arguments are also particular of the option selected as the first argument, i.e, the rest of arguments are related with the first one. So I thought I could independently parse these arguments with:

cl::liststd::string Argv (cl::ConsumeAfter, cl::desc("…"));

But, doing this when I run:
myTool option1 file.cpp –
I got the next error:

“error - this positional option will never be matched, because it does not Require a value and a cl::ConsumeAfter option is active!”

So, I modify “OptionsLevelOptionsLevel” including the cl::Required flagThe error is now:

“option: does not allow a value! option1 specified.
option: must be specified at least once!
option: must be specified at least once!
option: must be specified at least once!”

Then, I decided to use cl::PositionalEatsArgs instead of cl::ConsumeAfter. Then, this is the result:

“option: does not allow a value! option1 specified.”

But, this time, the program continues. However, if I run “myTool option3 arg1 file.cpp --” it
gives me a different problem:

"warning: …/build/arg1: ‘linker’ input unused

error: unable to handle compilation, expected exactly one compiler job in ’ '"

But the program still goes on.

Is there a way to accomplish what I have explained? I don’t want those errors and warnings.

Thanks,

Pedro.